feedback1e WQ: healer tests cast every skill while blocking; rule in headers

Review follow-up for E2 (not reproduced, no behaviour change):
- blockRun fills the skill's SP (and puts the patient back to 5 %) the
  first tick the healer blocks, and tests 2 and 3 assert the skill is
  cast or running while it blocks: all 56 healer loadouts now cast in
  the window (half never did at the default initial SP).
- The reported 炎 boss round makes 录武官's skill ready when she first
  holds 卢西恩 / 不祥幻影 and asserts it is cast or running then.
- The boss test says what it covers: 0 healer damage on all 20 boss /
  hidden fields; healers block 卢西恩 / 不祥幻影 (h07_05) and a
  patrolling 碎铳之簧 once its shield is broken (h08_02); the other
  leaders and parts cannot be blocked by a block-1 unit.
- SIM.md: the healer qualifier follows the "one-line flip" sentence, so
  "This replaces..." refers to the every-blocker rule again.
- ai.js header, Battle.blockedTargets and targeting.js: the blocked-first
  rule is for attacks that hit enemies; a heal attack keeps selecting
  injured allies (PRTS 卫戍协议/帮助).
- PLAYING.md: the healer exception names 咒愈师 as the one that hits.

server/sim/targeting.js

@@ -6,7 +6,8 @@
 // occupies is (body.js; user playtest #5 item 10). `rangeExtend` (ability_range_forward_extend) adds N tiles
 // past the furthest cell of every row, along +dCol BEFORE rotating (DESIGN §3).
 // Operator priority: (1) enemies it blocks (every blocker, ranged ones on melee tiles included — user playtest #6
-// follow-up "阻挡了就一定要能打到"; Battle.blockedTargets), (2) profile priority (fly/lowDef/…),
+// follow-up "阻挡了就一定要能打到"; Battle.blockedTargets; a healer's heal attack picks injured allies instead, blocking
+// or not — ai.js acquireTargets), (2) profile priority (fly/lowDef/…),
 // (3) higher enemy taunt, (4) least remaining path distance to the goal, (5) earliest spawned. Air units
 // (Unit.isFlying: FLY, 近地悬浮, 浮空) need a profile that can hit them (`canHitFly`, never `groundOnly`). Enemy
 // priority: sortAllyTargets.